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OBJECTIVE--Whether dietary habits early in life can affect risk of type 2 diabetes (T2DM) in adulthood is unknown. We evaluated the relationship between dietary patterns during adolescence and risk of [...]

Background: Few studies have evaluated the cost of a diet that may prevent cardiovascular disease. High scores on the Alternative Healthy Eating Index (AHEI) have been associated with lower rates of cardiovascular disease. Objective: We sought to evaluate the cost of a dietary pattern that may prevent cardiovascular disease among women residing in the United States. Design: By using food-cost data from the US Department of Agriculture, we explored relations between spending on food and AHEI scores among 78,191 participants in the Nurses' Health Study. By using linear regression, we estimated the change in AHEI score (range: 2.5-87.5) for a $1 increase in spending on various food groups. Results: Study participants in the highest energy-adjusted spending quintile spent 124% as much money each day as those in the lowest quintile. The difference in AHEI scores (10th-90th percentile) between all study participants was 30 index points (Spearman's correlation coefficient between total spending and AHEI = 0.44). The difference in AHEI scores (10th-90th percentile) within each quintile of spending ranged from 25 to 29 index points. Greater spending on nuts, soy and beans, and whole grains was associated with a high-er AHEI score. Greater spending on red and processed meats and high-fat dairy was associated with a lower AHEI score. Conclusions: Although spending more money was associated with a healthier diet, large improvements in diet may be achieved without increased spending. The purchase of plant-based foods may offer the best investment for dietary health. doi: 10.3945/ajcn.2010.29854

Background: Little is known about the effectiveness of behavioral strategies to prevent long-term weight gain among adolescents and young adults. Objective: The objective was to assess the relation of dietary and physical activity weight-control strategies, alone and together, with subsequent weight change. Design: This was a prospective study of 4456 female adolescents and young adults aged 14-22 y in the ongoing Growing Up Today Study. Weight-control behaviors, including dietary approaches and physical activity, were self-reported in 2001 and were used to predict weight change from 2001 to 2005. Results: In 2001-2002, 23.7% of female adolescents and young adults were trying to maintain their weight and another 54.4% were trying to lose weight. Approximately 25% used each of the following weight-control strategies: not eating snacks, following lowcalorie or low-fat diets, and limiting portion sizes. In addition, 47.7% reported exercising at least occasionally for weight control. During 4 y of follow-up, participants gained an average of 3.3 kg. None of the dietary approaches to weight control predicted less weight change; however, females who exercised >5 d/wk gained significantly less weight than did their peers (-0.9 kg; 95% CI: -1.4, -0.4). The most successful strategy for weight-gain prevention among the females was to limit portion sizes (- 1.9 kg; 95% CI: -2.6, -1.1) combined with frequent exercise. Conclusions: Our results suggest that physical activity is a necessary strategy for long-term weight control among adolescents and young adult females. Combining dietary weight-control approaches with physical activity is the most effective method for reducing weight gain. doi: 10.3945/ajcn.2009.28321.

Background: Evidence from observational studies suggests that inadequate folate status enhances colorectal carcinogenesis, but results from some randomized trials do not support this hypothesis. Objective: To assess the effect of folic acid supplementation on recurrent colorectal adenoma, we conducted a cost-efficient, double-blind, randomized trial among participants of 2 large prospective cohorts, the Health Professionals Follow-Up Study and the Nurses' Health Study. Design: Participants were randomly assigned to receive folic acid (1 mg/d) (n = 338) or placebo (n = 334) for 3-6.5 y. The primary endpoint was any new diagnosis of adenoma during the study period (May 1996-March 2004). Secondary outcomes were adenoma by site and stage and number of recurrent adenomas. Associations were also examined by plasma folate concentrations at baseline. Results: Incidence of at least one recurrent adenoma was not significantly associated with folic acid supplementation [relative risk (RR): 0.82; 95% CI: 0.59,1.13; P = 0.22]. Among participants with low plasma folate concentrations at baseline ([less than or equal to] 7.5 ng/mL), those randomly assigned to receive folic acid experienced a significant decrease in adenoma recurrence (RR: 0.61; 95% CI: 0.42, 0.90; P = 0.01), whereas for subjects with high folate concentrations at baseline (>7.5 ng/mL), supplemental folic acid had no significant effect (RR: 1.28; 95% CI: 0.82, 1.99; P = 0.27, [P.sub.interaction] = 0.01). Contrary to findings from another clinical trial, there was no evidence for an increased risk of advanced or multiple adenomas. Conclusions: Our results do not support an overall protective effect of folic acid supplementation on adenoma recurrence. Folic acid supplementation may be beneficial among those with lower folate concentrations at baseline. This trial was registered at clinical trials. gov as NCT00512850. Am J Clin Nutr 2009;90:1623-31. DOI: 10.3945/ajcn.2009.28319

Background: Greater fish and omega-3 (n--3) polyunsaturated fatty acid (PUFA) intake may reduce dementia risk; however, previous studies have reported conflicting results, which were largely based on short-term follow-up. Objective: The objective was to study the dietary consumption of fish and omega-3 PUFAs in relation to long-term dementia risk. Design: We studied 5395 participants aged [greater than or equal to] 55 y in the Rotterdam Study who were free of dementia and reported dietary information at baseline. We used age- and sex-adjusted Cox proportional hazard and multivariate-adjusted models to evaluate the relative risk of dementia and Alzheimer disease (AD) across categories of typical fish intake (none, low, and high) and fish type consumed (none, lean, and fatty). We also evaluated dementia and AD risk across tertiles of omega-3 PUFA intake, specifically, total long-chain omega-3 fatty acids: eicosapentaenoic acid (EPA) + docosahexaenoic acid (DHA), [alpha]-linolenic acid, and EPA and DHA individually. Results: During an average follow-up of 9.6 y, dementia developed in 465 participants (365 with a diagnosis of AD). In multivariate-adjusted models, total fish intake was unrelated to dementia risk (P for trend = 0.7). Compared with participants who typically ate no fish, those with a high fish intake had a similar dementia risk (hazard ratio: 0.95; 95% CI: 0.76, 1.19), as did those who typically ate fatty fish (hazard ratio: 0.98; 95% CI: 0.77, 1.24). Dietary intakes of omega-3 PUFAs were also not associated with dementia risk, and the results were similar when we considered AD specifically. Conclusion: In this Dutch cohort, who had a moderate consumption of fish and omega-3 PUFAs, these dietary factors do not appear to be associated with long-term dementia risk.

OBJECTIVE--Individuals with type 2 diabetes have high risk of late-life cognitive impairment, yet little is known about strategies to modify risk. Targeting insulin resistance and vascular complications--both associated with cognitive [...]

Background Breast cancer incidence is currently low in China. However, the distribution of reproductive and lifestyle risk factors for breast cancer among Chinese women is changing rapidly. We quantified the expected effect of changes in breast cancer risk factors on future rates of breast cancer in China. Methods We first validated and calibrated the Rosner-Colditz log-incidence breast cancer model in Chinese women who participated in the Shanghai Women's Health Study cohort (N = 74942). We then applied the calibrated model to a representative sample of Chinese women who were aged 35-49 years in 2001 using data from the Chinese National Family Planning and Reproductive Health Survey (NFPRHS, N = 17078) to predict the age-specific and cumulative breast cancer incidence among all Chinese women of this age group. We evaluated the relative impact of changes in modifiable risk factors, including alcohol intake, parity, postmenopausal hormone use, and adult weight gain, on cumulative incidence of breast cancer. Results Breast cancer incidence in China is expected to increase substantially from current rates, estimated at 10-60 cases per 100000 women, to more than 100 new cases per 100000 women aged 55-69 years by 2021. We predicted 2.5 million cases of breast cancer by 2021 among Chinese women who were 35-49 years old in 2001. Modest reductions in hormone and alcohol use, and weight maintenance could prevent 270000 of these cases. Conclusions China is on the cusp of a breast cancer epidemic. Although some risk factors associated with economic development are largely unavoidable, the substantial predicted increase in new cases of breast cancer calls for urgent incorporation of this disease in future health care infrastructure planning.

Background: The association between lutein/zeaxanthin intake and age-related macular degeneration (AMD) risk may differ by smoking status, vitamin C and E intakes, and body fatness. Objective: The objective was to evaluate the association between lutein/zeaxanthin intake and AMD risk by smoking status, intake of antioxidant vitamins, and body fatness. Design: We conducted a prospective follow-up study of 71 494 women and 41 564 men aged [greater than or equal to] 50 y and had no diagnosis of AMD or cancer. Diet was assessed with a validated semiquantitative food-frequency questionnaire. Results: During up to 18 y of follow-up, we documented 673 incident cases of early AMD and 442 incident cases of neovascular AMD with a visual loss of 20/30 or worse due primarily to AMD. Lutein/zeaxanthin intake was not associated with the risk of self-reported early AMD. There was a statistically nonsignificant and nonlinear inverse association between lutein/zeaxanthin intake and neovascular AMD risk; the pooled multivariate relative risks for increasing quintiles of intake were 1.00 (referent), 0.80, 0.84, 0.97, and 0.72 (95% CI: 0.53, 0.99) (P for trend = 0.14). For early AMD, the association with lutein/zeaxanthin intake did not vary by smoking status, intakes of vitamins C and E, or body mass index. For neovascular AMD, a nonlinear inverse association was found among never smokers. Conclusions: These data do not support a protective role of lutein/zeaxanthin intake on risk of self-reported early AMD. The suggestion of inverse associations related to the risk of neovascular AMD needs to be examined further.

Background Physical activity has been consistently associated with lower risk of postmenopausal breast cancer, but its relationship with premenopausal breast cancer is unclear. We investigated whether physical activity is associated with reduced incidence of premenopausal breast cancer, and, if so, what age period and intensity of activity are critical. Methods A total of 64777 premenopausal women in the Nurses' Health Study II reported, starting on the 1997 questionnaire, their leisure-time physical activity from age 12 to current age. Cox regression models were used to examine the relationship between physical activity, categorized by age period (adolescence, adulthood, and lifetime) and intensity (strenuous, moderate, walking, and total), and risk of invasive premenopausal breast cancer. Results During 6 years of follow-up, 550 premenopausal women developed breast cancer. The strongest associations were for total leisure-time activity during participants' lifetimes rather than for any one intensity or age period. Active women engaging in 39 or more metabolic equivalent hours per week (MET-h/wk) of total activity on average during their lifetime had a 23% lower risk of premenopausal breast cancer (relative risk = 0.77; 95% confidence interval = 0.64 to 0.93) than women reporting less activity. This level of total activity is equivalent to 3.25 h/wk of running or 13 h/wk of walking. The age-adjusted incidence rates of breast cancer for the highest ([greater than or equal to] 54 MET-h/wk) and lowest ( Conclusions Leisure-time physical activity was associated with a reduced risk for premenopausal breast cancer in this cohort. Premenopausal women regularly engaging in high amounts of physical activity during both adolescence and adulthood may derive the most benefit.

Background: Nutrients in dietary fruit and vegetables have been hypothesized to lower the risk of glioma by reducing the endogenous formation of N-nitroso compounds. Studies examining fruit and vegetable consumption and brain tumors have retied on case-control study designs, with one exception, and results have been inconsistent. Objective: We prospectively examined the relation between consumption of fruit and vegetables (and specifically carotenoids) and the risk of glioma among men and women in 3 large US cohort studies: the Health Professionals Follow-Up Study (HPFS), the Nurses' Health Study I (NHS I), and NHS II. Design: Dietary intake was assessed by food-frequency questionnaires obtained at baseline and updated every 4 y through 2002 (HPFS and NHS I) or 2003 (NHS II). We identified 296 incident adult gliomas during 3 669 589 person-years of follow-up. Cox proportional hazard models were used to estimate incidence rate ratios (RR) and 95% CIs between intake of fruit, vegetables, and carotenoids and glioma risk, with adjustment for age and total caloric intake. Results: Updated average consumption of total fruit and vegetables was not significantly associated with glioma risk in the men and women (pooled multivariate RR in a comparison of the highest with the lowest quintile: 1.12; 95% CI: 0.74, 1.69). Other fruit and vegetable subgroups, individual fruit and vegetables, and 5 major carotenoids were not significantly associated with risk of glioma. Conclusion: Our findings suggest that fruit, vegetable, and carotenoid consumption is not likely associated strongly with the risk of adult glioma. Am J Clin Nutr 2007;85:877-86. KEY WORDS Fruit, vegetables, glioma, prospective studies, epidemiology

Background: Pharmacologic activation of the peroxisome proliferator-activated receptor [gamma] (PPAR-[gamma]) improves ovulatory function in women with polycystic ovary syndrome, and specific dietary fatty acids can affect PPAR-[gamma] activity. Objective: The objective of the study was to assess whether the intakes of total fat, cholesterol, and major types of fatty acids affect the risk of ovulatory infertility. Design: We conducted a prospective cohort study of 18 555 married, premenopausal women without a history of infertility who attempted a pregnancy or became pregnant between 1991 and 1999. Diet was assessed twice during follow-up by using a food-frequency questionnaire. Results: During follow-up, 438 incidents of ovulatory infertility were reported. In logistic regression analyses, intakes of total fat, cholesterol, and most types of fatty acids were not related to ovulatory infertility. Each 2% increase in the intake of energy from trans unsaturated fats, as opposed to that from carbohydrates, was associated with a 73% greater risk of ovulatory infertility after adjustment for known and suspected risk factors for this condition [relative risk (RR) = 1.73; 95% CI: 1.09, 2.73]. Obtaining 2% of energy intake from trans fats rather than from n-6 polyunsaturated fats was associated with a similar increase in the risk of ovulatory infertility (RR = 1.79; 95% CI: 1.11, 2.89). In addition, obtaining 2% of energy from trans fats rather than from monounsaturated fats was associated with a more than doubled risk of ovulatory infertility (RR = 2.31; 95% CI: 1.09, 4.87). Conclusion: trans Unsaturated fats may increase the risk of ovulatory infertility when consumed instead of carbohydrates or unsaturated fats commonly found in nonhydrogenated vegetable oils KEY WORDS Diet, dietary fatty acids, infertility, ovulation, reproductive medicine, nutritional epidemiology

Background: The role of calcium in the maintenance of body weight remains controversial. Objective: We investigated the association between calcium and dairy intakes and 12-y weight change in US men. Design: This study was conducted with the use of data from the Health Professionals Follow-up Study, a prospective cohort of men aged 40-75 y in 1986. Data on lifestyle factors and diet were updated biennially with self-administered questionnaires. The participants reported their body weight in 1986 and in 1998. The outcome in our study was 12-y weight change. We used multivariate linear regression to examine how baseline calcium intake (n = 23 504) and change in calcium intake (n = 19 615) were associated with weight change. Because dairy foods are the predominant source of calcium in the diet, we also evaluated a similar association with dairy intake. Results: In a multivariate analysis with adjustment for potential confounders, baseline or change in intake of total calcium was not significantly associated with weight change. In addition, we did not find any association with dietary, dairy, or supplemental calcium intake when evaluated separately. The men with the largest increase in total dairy intake gained slightly more weight than did the men who decreased intake the most (3.14 compared with 2.57 kg; P for trend = 0.001). This association was primarily due to an increase in high-fat dairy intake. Low-fat dairy intake was not significantly associated with weight change. Conclusion: Our data do not support the hypothesis that an increase in calcium intake or dairy consumption is associated with lower long-term weight gain in men. KEY WORDS Calcium, dairy intake, weight change

Background: Studies of fruit and vegetable consumption in relation to overall health are limited. We evaluated the relationship between fruit and vegetable intake and the incidence of cardiovascular disease and cancer and of deaths from other causes in two prospective cohorts. Methods: A total of 71 910 female participants in the Nurses' Health study and 37 725 male participants in the Health Professionals' Follow-up Study who were free of major chronic disease completed baseline semiquantitative food-frequency questionnaires in 1984 and 1986, respectively. Dietary information was updated in 1986, 1990, and 1994 for women and in 1990 and 1994 for men. Participants were followed up for incidence of cardiovascular disease, cancer, or death through May 1998 (women) and January 1998 (men). Multivariable-adjusted relative risks were calculated with Cox proportional hazards analysis. Results: We ascertained 9329 events (1964 cardiovascular, 6584 cancer, and 781 other deaths) in women and 4957 events (1670 cardiovascular diseases, 2500 cancers, and 787 other deaths) in men during follow-up. For men and women combined, participants in the highest quintile of total fruit and vegetable intake had a relative risk for major chronic disease of 0.95 (95% confidence interval [CI] = 0.89 to 1.01) times that of those in the lowest. Total fruit and vegetable intake was inversely associated with risk of cardiovascular disease but not with overall cancer incidence, with relative risk for an increment of five servings daily of 0.88 (95% CI = 0.81 to 0.95) for cardiovascular disease and 1.00 (95% CI = 0.95 to 1.05) for cancer. Of the food groups analyzed, green leafy vegetable intake showed the strongest inverse association with major chronic disease and cardiovascular disease. For an increment of one serving per day of green leafy vegetables, relative risks were 0.95 (95% CI = 0.92 to 0.99) for major chronic disease and 0.89 (95% CI = 0.83 to 0.96) for cardiovascular disease. Conclusions: Increased fruit and vegetable consumption was associated with a modest although not statistically significant reduction in the development of major chronic disease. The benefits appeared to be primarily for cardiovascular disease and not for cancer.

Background: Recent case-control studies suggest that, given equal smoking exposure, women may have a higher relative risk of developing lung cancer than men. Despite prospective data that conflict with this hypothesis, mechanistic studies to find a biologic basis for a sex difference continue. Methods: We addressed the hypothesis directly by analyzing prospective data from former and current smokers in two large cohorts--the Nurses' Health Study of women and the Health Professionals Follow-up Study of men. We calculated incidence rates and hazard ratios of lung cancer in women compared with men, adjusting for age, number of cigarettes smoked per day, age at start of smoking, and time sine quitting, using Cox proportional hazards models. We also reviewed published results from prospective analyses. Results: From 1986 through 2000, 955 and 311 primary lung cancers were identified among 60 296 women and 25 397 men, respectively, who ranged in age from 40 to 79 years. Incidence rates per 100 000 person-years for women and men were 253 and 232, respectively, among current smoker and 81 and 73, respectively, among former smokers. The hazard ratio in women ever smokers compared with men was 1.11 (95% confidence interval = 0.95 to 1.31). Six published prospective cohort studies allowed assessment of comparative susceptibility to lung cancer by sex. None supported an excess risk of lung cancer for women. Conclusions: Women do not appear to have a greater susceptibility to lung cancer than men, given equal smoking exposure. Research should be focused on enhancing preventive interventions for all.

Background: Prostaglandin [F.sub.2[alpha]] analogues are effective intraocular-pressure-lowering drugs. Dietary fatty acids affect endogenous prostaglandin [F.sub.2[alpha]] concentrations and may thus influence intraocular pressure. Objective: We prospectively examined dietary fat consumption in relation to primary open-angle glaucoma (POAG). Design: Women (n = 76 199 in the Nurses' Health Study) and men (n = 40 306 in the Health Professionals Follow-Up Study) free of POAG in 1980 and 1986, respectively, were followed until 1996 if they were [greater than or equal to] 40 y old and reported receiving eye exams during follow-up. Potential confounders were assessed on biennial questionnaires, and energy-adjusted cumulative averaged fat intakes were measured by using validated food-frequency questionnaires. We analyzed 474 self-reported POAG cases confirmed by medical chart review. Cohort-specific multivariate rate ratios (RRs) were obtained by using proportional hazards models and were then pooled. Results: Major fats and fat subtypes were not independently associated with POAG risk. Pooled multivariate RRs (95% CI) for POAG comparing the highest with the lowest quintile of fat intake were as follows: 0.90 (0.67, 1.21) for total fat, 1.03 (0.77, 1.38) for saturated fat, 0.76 (0.56, 1.03) for monounsaturated fat, and 0.87 (0.66, 1.16) for polyunsaturated fat, none of which were statistically significant. We found a suggestive positive association between a higher ratio of n-3 to n-6 polyunsaturated fat and risk of POAG [RR = 1.49 (1.11, 2.01); P for trend = 0.10], which was stronger for high-tension POAG [RR = 1.68 (1.18, 2.39); P for trend = 0.009]. Conclusion: A high ratio of n-3 to n-6 polyunsaturated fat appears to increase the risk of POAG, particularly high-tension POAG. Further studies are needed. KEY WORDS Primary open-angle glaucoma, dietary fats, unsaturated fatty acids, food-frequency questionnaire, Nurses' Health Study, Health Professionals Follow-Up Study, prospective studies

Background: Evaluations of epidemiologic risk factors in relation to breast cancer classified jointly by estrogen receptor (ER) and progesterone receptor (PR) status have been inconsistent. To address this issue, we conducted a prospective evaluation of risk factors for breast cancer classified according to receptor status. Methods: During 1 029 414 person-years of follow-up of 66 145 women participating in the Nurses' Health Study from 1980 through 2000, we identified 2096 incident cases of breast cancer for which information on ER/PR status was available: 1281 were ER+/ PR+, 318 were ER+/PR-, 80 were ER-/PR+, and 417 were ER-/PR-. We fit a log-incidence model of breast cancer and used polychotomous logistic regression to compare coefficients for breast cancer risk factors in patients with different ER/PR status. To test for differences in risk factor odds ratios based on marginal ER/PR categories, we evaluated ER status controlling for PR status and vice versa. The predictive ability of our log-incidence model to discriminate between women who would develop ER+/PR+ breast cancer and those who would not (and similarly for ER-/ PR- breast cancer) was evaluated by using receiver operator characteristic curve analysis. All statistical tests were two-sided. Results: We observed statistically significant heterogeneity among the four ER/PR categories for some risk factors (age, menopausal status, body mass index [BMI] after menopause, the one-time adverse effect of first pregnancy, and past use of postmenopausal hormones) but not for others (benign breast disease, family history of breast cancer, alcohol use, and height). The one-time adverse association of first pregnancy with incidence was present for PR- but not for PR+ tumors after controlling for ER status (P = .007). However, the association of BMI after menopause with incidence was present for PR+ but not PR- tumors (P = .005). Statistically significant differences in the incidence of ER+ and ER- tumors were seen with age, both before and after menopause (P = .003), and with past use of postmenopausal hormones (P = .01). Area under the receiver operator characteristic curve, adjusted for age, was 0.64 (95% confidence interval [CI] = 0.63 to 0.66) for ER+/PR+ tumors and 0.61 (95% CI = 0.58 to 0.64) for ER-/PR- tumors. Conclusions: Incidence rates and risk factors for breast cancer differ according to ER and PR status. Thus, to accurately estimate breast cancer risk, breast cancer cases should be divided according to the ER and PR status of the tumor.

Background: Although increased consumption of dietary fiber and grain products is widely recommended to maintain healthy body weight, little is known about the relation of whole grains to body weight and long-term weight changes. Objective: We examined the associations between the intakes of dietary fiber and whole- or refined-grain products and weight gain over time. Design: In a prospective cohort study, 74 091 US female nurses, aged 38-63 y in 1984 and free of known cardiovascular disease, cancer, and diabetes at baseline, were followed from 1984 to 1996; their dietary habits were assessed in 1984, 1986, 1990, and 1994 with validated food-frequency questionnaires. Using multiple models to adjust for covariates, we calculated average weight, body mass index (BMI; in kg/[m.sup.2]), long-term weight changes, and the odds ratio of developing obesity (BMI [greater than or equal to] 30) according to change in dietary intake. Results: Women who consumed more whole grains consistently weighed less than did women who consumed less whole grains (P for trend < 0.0001). Over 12 y, those with the greatest increase in intake of dietary fiber gained an average of 1.52 kg less than did those with the smallest increase in intake of dietary fiber (P for trend < 0.0001) independent of body weight at baseline, age, and changes in covariate status. Women in the highest quintile of dietary fiber intake had a 49% lower risk of major weight gain than did women in the highest quintile (OR = 0.51; 95% CI: 0.39, 0.67; P < 0.0001 for trend). Conclusion: Weight gain was inversely associated with the intake of high-fiber, whole-grain foods but positively related to the intake of refined-grain foods, which indicated the importance of distinguishing whole-grain products from refined-grain products to aid in weight control. KEY WORDS Whole grains, refined grains, dietary fiber, body weight, prospective study, obesity, weight gain, women

Abstract Objective To examine the association between intake of total fat, specific types of fat, and cholesterol and risk of stroke in men. Design and setting Health professional follow up [...]

Background: Although it is known that abdominal obesity increases the risk of chronic diseases, prospective data examining the relation between lifestyle factors and the accumulation of abdominal adipose tissue are sparse. Objective: The objective of the study was to determine the associations of changes in diet, physical activity, alcohol consumption, and smoking with 9-y waist gain among US men. Design: A prospective cohort comprised 16 587 US men aged 40-75 y at baseline in 1986. Data on lifestyle factors were provided periodically with the use of self-reported questionnaires, and participants measured and reported their waist circumference in 1987 and 1996. Results: In multivariate analyses, a 2% increment in energy intake from trans fats that were isocalorically substituted for either polyunsaturated fats or carbohydrates was significantly associated with a 0.77-cm waist gain over 9 y (P < 0.001 for each comparison). An increase of 12 g total fiber/d was associated with a 0.63-cm decrease in waist circumference (P < 0.001), whereas smoking cessation and a 20-h/wk increase in television watching were associated with a 1.98-cm and 0.59-cm waist gain, respectively (P < 0.001). Increases of 25 metabolic equivalent tasks (METs) h/wk in vigorous physical activity and of [greater than or equal to] 0.5 h/wk in weight training were associated with 0.38-cm and 0.91-cm decreases in waist circumference, respectively (P < 0.001 for each comparison). These associations remained significant after further adjustment for concurrent change in body mass index. Changes in total fat and alcohol consumption and in walking volume were not significantly related to waist gain. Conclusions: Waist gain may be modulated by changes in trans fat and fiber consumption, smoking cessation, and physical activity. KEY WORDS Dietary fat, trans fats, fiber, physical activity, smoking, waist gain, obesity

OBJECTIVE -- Hyperinsulinemia may promote mammary carcinogenesis. Insulin resistance has been linked to an increased risk of breast cancer and is also characteristic of type 2 diabetes. We prospectively evaluated [...]

Background: Physiologic evidence suggests that use of alcohol increases the risk for breast cancer through a hormonal mechanism, but the relationship among breast cancer, alcohol, and postmenopausal hormones (PMH) remains unclear. Objective: To examine the relation between concurrent use of alcohol and PMH and invasive breast cancer. Design: Prospective cohort study. Setting: NursesE Health Study. Participants: 44 187 postmenopausal women. Measurements: Self-reported data on PMH use and breast cancer obtained from biennial questionnaires completed from 1980 to 1994 and average alcohol consumption in 1980, 1984, 1986, and 1990. Results: 1722 women developed invasive breast cancer. Risk for breast cancer was elevated in women who currently used PMH for 5 or more years and did not drink alcohol (relative risk, 1.32 [95% CI, 1.05 to 1.66]) and those who never used PMH but drank 20 or more g (1.5 to 2 drinks) of alcohol daily (relative risk, 1.28 [CI, 0.97 to 1.69]). Current users of PMH for 5 or more years who consumed 20 or more g of alcohol daily had a relative risk for breast cancer nearly twice (1.99 [CI, 1.42 to 2.79]) that of non-drinking nonusers of PMH. A hypothetical postmenopausal woman whose lifetime risk for breast cancer is 4% could increase her risk to 8% with 5 or more years of current PMH use and consumption of more than one alcoholic drink daily. Conclusions: Both alcohol consumption and PMH use were associated with an increased incidence of breast cancer. Women who are currently taking PMH may want to consider the added risks of regular alcohol consumption.

Background: High intake of folate may reduce risk for colon cancer, but the dosage and duration relations and the impact of dietary compared with supplementary sources are not well understood. Objective: To evaluate the relation between folate intake and incidence of colon cancer. Design: Prospective cohort study. Setting: 88 756 women from the Nurses' Health Study who were free of cancer in 1980 and provided updated assessments of diet, including multivitamin supplement use, from 1980 to 1994. Patients: 442 women with new cases of colon cancer. Measurements: Multivariate relative risk (RR) and 95% CIs for colon cancer in relation to energy-adjusted folate intake. Results: Higher energy-adjusted folate intake in 1980 was related to a lower risk for colon cancer (RR, 0.69 [95% CI, 0.52 to 0.93] for intake [is greater than] 400 [micro]g/d compared with intake [is less than or equal to] 200 [micro]g/d) after controlling for age; family history of colorectal cancer; aspirin use; smoking; body mass; physical activity; and intakes of red meat, alcohol, methionine, and fiber. When intake of vitamins A, C, D, and E and intake of calcium were also controlled for, results were similar. Women who used multivitamins containing folic acid had no benefit with respect to colon cancer after 4 years of use (RR, 1.02) and had only nonsignificant risk reductions after 5 to 9 (RR, 0.83) or 10 to 14 years of use (RR, 0.80). After 15 years of use, however, risk was markedly lower (RR, 0.25 [CI, 0.13 to 0.51]), representing 15 instead of 68 new cases of colon cancer per 10 000 women 55 to 69 years of age. Folate from dietary sources alone was related to a modest reduction in risk for colon cancer, and the benefit of long-term multivitamin use was present across all levels of dietary intakes. Conclusions: Long-term use of multivitamins may substantially reduce risk for colon cancer. This effect may be related to the folic acid contained in multivitamins., Women who take a multivitamin tablet that contains folic acid may reduce their risk of colon cancer. Researchers analyzed the incidence of colon cancer over a 15-year period in the 88,756 women participating in the Nurses' Health Study. Although women who took multivitamins had no lower risk of colon cancer in the short term, after 15 years of vitamin use their risk was 75% lower than that in women who did not take vitamins. This benefit is most likely due to the folic acid in the supplements.

Background: Obesity increases the risk for hypertension, but the effects of modest long-term weight changes have not been precisely quantified. Objective: To investigate body mass index (BMI) and weight change in relation to risk for hypertension. Design: Cohort study. Setting: General community. Participants: Cohort of 82 473 U.S. female nurses 30 to 55 years of age followed every 2 years since 1976. The follow-up rate was 95%. Measurements: Primary risk factors examined were 1) BMI at age 18 years and midlife and 2) long-term and medium-term weight changes. The outcome was incident cases of hypertension. Results: By 1992, 16 395 incident cases of hypertension had been diagnosed. After adjustment for multiple covariates, BMI at 18 years of age and midlife were positively associated with occurrence of hypertension (P for trend [is less than] 0.001). Long-term weight loss after 18 years of age was related to a significantly lower risk for hypertension, and weight gain dramatically increased the risk for hypertension (compared with weight change [is less than or equal to] 2 kg, multivariate relative risks were 0.85 for a loss of 5.0 to 9.9 kg, 0.74 for a loss [is greater than or equal to] 10 kg, 1.74 for a gain of 5.0 to 9.9 kg, and 5.21 for a gain [is greater than or equal to] 25.0 kg). Among women in the top tertile of baseline BMI at age 18 years, weight loss had a greater apparent benefit. The association between weight change and risk for hypertension was stronger in younger ([is greater than or equal to] 45 years of age) than older women ([is greater than or equal to] 55 years of age). Medium-term weight changes after 1976 showed similar relations to risk for hypertension. Conclusions: Excess weight and even modest adult weight gain substantially increase risk for hypertension. Weight loss reduces the risk for hypertension., Women may lower their risk of hypertension by losing weight. Researchers analyzed weight loss, weight gain and the risk of hypertension in 82,473 women participating in the Nurses' Health Study, which was begun in 1976. Long-term weight loss after the age of 18 substantially lowered the risk of hypertension, while weight gain increased the risk. The benefit of weight loss was greater among women who weighed the most at the age of 18. The association between weight gain and hypertension was strongest in women younger than 45 years old.

Background: Breast cancer mortality and incidence rates vary by geographic region in the United States. Previous analytic studies have measured mortality, not incidence, and have used regional prevalences to control for geographic variation in risk factors rather than adjusting for risk factors measured at the level of the individual. We prospectively evaluated regional variation in breast cancer incidence rates in the Nurses' Health Study and assessed the influence of breast cancer risk factors measured at the individual level. Methods: The Nurses' Health Study cohort was established in 1976 when 121700 female nurses aged 30-55 years living in 11 U.S. states were enrolled. These states represent all four regions of the continental United States. We identified 3603 incident cases of invasive breast cancer through 1992 (1794565 person-years of follow-up). We calculated relative risks (RRs) adjusted for age and for age and established risk factors (i.e., multivariate-adjusted analysis), comparing California, the Northeast, and the Midwest with the South. Results: For premenopausal women, there was little evidence of regional variation in breast cancer incidence rates, either in age-adjusted or in multivariate-adjusted analyses. For postmenopausal women in California, age-adjusted risk was modestly elevated (RR = 1.24; 95% confidence interval [CI] = 1.05-1.47); after adjusting for age and for established risk factors, the excess rate in California was attenuated by 25% (RR = 1.18; 95% CI = 1.00-1.40). No excess of breast cancer incidence was observed for postmenopausal women in either the Northeast or the Midwest. Conclusions: Little regional variation in age-adjusted breast cancer incidence rates was observed, with the exception of a modest excess for postmenopausal women in California. Adjustment for differences in the distribution of established risk factors explained some of the excess risk in California. [J Natl Cancer Inst 1997; 89:1373-8]

Abstract Objective: To examine the association between birth weight and non-fatal adult cardiovascular disease while controlling for potential confounders such as socioeconomic group and adult lifestyle. Design: Retrospective self report [...]

Regression calibration is a statistical method for adjusting point and interval estimates of effect obtained from regression models commonly used in epidemiology for bias due to measurement error in assessing nutrients or other variables. Previous work developed regression calibration for use in estimating odds ratios from logistic regression. We extend this here to estimating incidence rate ratios from Cox proportional hazards models and regression slopes from linear-regression models. Regression calibration is appropriate when a gold standard is available in a validation study and a linear measurement error with constant variance applies or when replicate measurements are available in a reliability study and linear random within-person error can be assumed. In this paper, the method is illustrated by correction of rate ratios describing the relations between the incidence of breast cancer and dietary intakes of vitamin A, alcohol, and total energy in the Nurses' Health Study. An example using linear regression is based on estimation of the relation between ultradistal radius bone density and dietary intakes of caffeine, calcium, and total energy in the Massachusetts Women's Health Study. Software implementing these methods uses SAS macros.